chromeos: provides client-id to clients

The id is necessary for single-process-mash so that the browser process can
know it's id and lookup windows (everything runs in the same process in
single-process-mash). Outside of single-process-mash the id is really only
useful for debugging.

BUG=756085
TEST=covered by tests

Change-Id: I3819c5492fe2bfeeb243c44c36cc948168824ab6
Reviewed-on: https://chromium-review.googlesource.com/c/1318447Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605867}

content/renderer/mus/renderer_window_tree_client.cc

@@ -188,6 +188,8 @@ void RendererWindowTreeClient::DestroyFrame(uint32_t frame_routing_id) {
   pending_frames_.erase(frame_routing_id);
 }
 
+void RendererWindowTreeClient::OnClientId(uint32_t client_id) {}
+
 void RendererWindowTreeClient::OnEmbed(
     ws::mojom::WindowDataPtr root,
     ws::mojom::WindowTreePtr tree,

content/renderer/mus/renderer_window_tree_client.h

@@ -110,6 +110,7 @@ class RendererWindowTreeClient : public ws::mojom::WindowTreeClient,
   // these will remain unimplemented in the long-term. Some of the
   // implementations would require some amount of refactoring out of
   // RenderWidget and related classes (e.g. resize, input, ime etc.).
+  void OnClientId(uint32_t client_id) override;
   void OnEmbed(
       ws::mojom::WindowDataPtr root,
       ws::mojom::WindowTreePtr tree,

services/ws/public/mojom/window_tree.mojom

@@ -418,6 +418,11 @@ interface WindowTree {
 // calling SetWindowBounds(), connection 1 does not receive
 // OnWindowBoundsChanged().
 interface WindowTreeClient {
+  // Sent when clients establishes a connection to the WindowService.
+  // |client_id| gives the unique id for the client. This value is generally
+  // only useful for debugging.
+  OnClientId(uint32 client_id);
+
   // Invoked when the client application has been embedded at |root|.
   // See Embed() on WindowTree for more details. |tree| will be a handle back to
   // the window manager service, unless the connection is to the root connection

services/ws/test_window_tree_client.cc

@@ -64,6 +64,8 @@ bool TestWindowTreeClient::AckFirstEvent(WindowTree* tree,
 
 void TestWindowTreeClient::OnChangeAdded() {}
 
+void TestWindowTreeClient::OnClientId(uint32_t client_id) {}
+
 void TestWindowTreeClient::OnEmbed(
     mojom::WindowDataPtr root,
     mojom::WindowTreePtr tree,

services/ws/test_window_tree_client.h

@@ -83,6 +83,7 @@ class TestWindowTreeClient : public mojom::WindowTreeClient,
   void OnChangeAdded() override;
 
   // mojom::WindowTreeClient:
+  void OnClientId(uint32_t client_id) override;
   void OnEmbed(
       mojom::WindowDataPtr root,
       mojom::WindowTreePtr tree,

services/ws/window_tree_binding.cc

@@ -62,6 +62,7 @@ void WindowTreeBinding::CreateBinding(
   binding_ = std::make_unique<mojo::Binding<mojom::WindowTree>>(
       window_tree_.get(), std::move(window_tree_request));
   binding_->set_connection_error_handler(std::move(connection_lost_callback));
+  window_tree_client_->OnClientId(window_tree_->client_id());
   window_tree_client_->GetScreenProviderObserver(
       MakeRequest(&screen_provider_observer_));
   window_service_->screen_provider()->AddObserver(

services/ws/window_tree_client_unittest.cc

@@ -162,6 +162,8 @@ class TestWindowTreeClient2 : public TestWindowTreeClient {
     binding_.Bind(std::move(request));
   }
 
+  ClientSpecificId client_id() const { return client_id_; }
+
   // Runs a nested MessageLoop until |count| changes (calls to
   // WindowTreeClient functions) have been received.
   void WaitForChangeCount(size_t count) {
@@ -277,6 +279,7 @@ class TestWindowTreeClient2 : public TestWindowTreeClient {
   };
 
   // TestWindowTreeClient:
+  void OnClientId(ClientSpecificId id) override { client_id_ = id; }
   void OnChangeAdded() override {
     if (wait_state_.get() &&
         tracker_.changes()->size() >= wait_state_->change_count) {
@@ -438,6 +441,7 @@ class TestWindowTreeClient2 : public TestWindowTreeClient {
   uint32_t waiting_change_id_;
   bool on_change_completed_result_;
   std::unique_ptr<base::RunLoop> change_completed_run_loop_;
+  ClientSpecificId client_id_ = 0u;
 
   DISALLOW_COPY_AND_ASSIGN(TestWindowTreeClient2);
 };
@@ -635,6 +639,10 @@ class WindowTreeClientTest : public WindowServerServiceTestBase {
   DISALLOW_COPY_AND_ASSIGN(WindowTreeClientTest);
 };
 
+TEST_F(WindowTreeClientTest, GotClientId) {
+  EXPECT_NE(0u, wt_client1_->client_id());
+}
+
 // Verifies two clients get different ids.
 TEST_F(WindowTreeClientTest, TwoClientsGetDifferentClientIds) {
   ASSERT_NO_FATAL_FAILURE(EstablishSecondClient(true));

ui/aura/mus/window_tree_client.cc

@@ -963,6 +963,10 @@ void WindowTreeClient::SetEventTargetingPolicy(
   tree_->SetEventTargetingPolicy(window->server_id(), policy);
 }
 
+void WindowTreeClient::OnClientId(uint32_t client_id) {
+  id_ = client_id;
+}
+
 void WindowTreeClient::OnEmbed(
     ws::mojom::WindowDataPtr root_data,
     ws::mojom::WindowTreePtr tree,

ui/aura/mus/window_tree_client.h

@@ -126,6 +126,8 @@ class AURA_EXPORT WindowTreeClient
   // Blocks until the initial screen configuration is received.
   bool WaitForDisplays();
 
+  const base::Optional<uint32_t>& id() const { return id_; }
+
   void SetCanFocus(Window* window, bool can_focus);
   void SetCanAcceptDrops(WindowMus* window, bool can_accept_drops);
   void SetEventTargetingPolicy(WindowMus* window,
@@ -363,6 +365,7 @@ class AURA_EXPORT WindowTreeClient
                                   std::unique_ptr<ui::PropertyData> data);
 
   // Overridden from WindowTreeClient:
+  void OnClientId(uint32_t client_id) override;
   void OnEmbed(
       ws::mojom::WindowDataPtr root,
       ws::mojom::WindowTreePtr tree,
@@ -589,6 +592,9 @@ class AURA_EXPORT WindowTreeClient
   mojo::AssociatedBinding<ws::mojom::ScreenProviderObserver>
       screen_provider_observer_binding_{this};
 
+  // Id for this connection. The server provides this value in OnClientId().
+  base::Optional<uint32_t> id_;
+
   base::WeakPtrFactory<WindowTreeClient> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeClient);